A merged PIN Schottky diode (MPS) is one example of the structure of a Schottky barrier diode (SBD). In the MPS, a depletion layer which is spread from an adjacent p-type layer is pinched off to reduce the electric field intensity of a Schottky electrode interface, which makes it possible to reduce a leakage current during reverse bias. In addition, an anode electrode comes into ohmic contact with the p-type layer. Therefore, when an anode voltage increases, holes are injected from the p-type layer and the conductivity of a drift layer is modulated. Therefore, the MPS has a high surge current resistance, similarly to the PIN diode.
In an MPS using silicon carbide (SiC), it is preferable to provide a silicide layer between a p-type layer and an anode electrode in order to bring the anode electrode into ohmic contact with the p-type layer. However, in this case, it is concern that degradation of characteristics, such as an increase in leakage current caused by the silicide layer will occur.